Liquid flask



FIG. 1 is a perspective view of a liquid flask of my claimed design;

FIG. 2 is a front elevational view thereof, the rear elevational viewbeing identical except for the unclaimed threads;

FIG. 3 is a right side elevational view thereof, the left sideelevational view identical except for the unclaimed threads;

FIG. 4 is a top plan view thereof; and,

FIG. 5 is a bottom plan view thereof.

The broken lines shown in the drawings are for environmental purposesonly and form no part of the claimed design.

The ornamental design for a liquid flask, as shown and described.